Conventionally, an ultrasound diagnostic apparatus is known which includes an ultrasound probe provided with an arrangement of a plurality of transducers, carries out scanning via an ultrasound beam with respect to a subject, such as a living body or the like, generates sound ray data sequentially from the received ultrasound, and generates and displays an ultrasound image based on the generated sound ray data.
In the case of the ultrasound diagnostic apparatus described above, for example, there is a heretofore known technique in which the value of interpolated data is determined in accordance with a difference between two echo data of the same depth on two adjacent ultrasound beams, and by forming a pseudo beam between the two ultrasound beams based on the determined value of interpolated data, the image size of an ultrasound image is changed (for example, this is described in Japanese Unexamined Patent Application Publication No. 08-299340).
However, in the case of the conventional technique described above, because there is a case in which accuracy of an image decreases when the image size of an ultrasound image is changed, resulted in a problem that the reliability of image decreases after changing the image size.